2010 Toyota Highlander Hybrid 7-Way Trailer Connector for Charging Trailer Battery

Question:

At the hitch, I need the base 4 wires plus the additional wire for charging the trailer battery. Hence, I assume I need a 7-pin connector at the hitch. The car has a white flat 4-pin connector in the rear wheel well. I could use the Curt 56042 to connect to that but that would only give me 4 wires. In addition, I cannot tell if there is that adapter under that dash if not, then I suppose I would need the Tek. 118449 package. If I get that all working and add the charging wire, what do I need to have the 7-wire plug at the hitch. Note that it would be nice if the charging wire was activated by ignition on so that the trailer battery would not drain the car battery. But, this is extra credit. I will have an expert install this but I want to have the right parts. Thx.

asked by: Bill S

Expert Reply:

Since you need to charge a trailer battery you are correct that you need to install a 7-way at the rear of your 2010 Toyota Highlander.

Since you have the correct connector for the part # 56042 to install you will need to use it as the base for your wiring. From there you will adapt it to a 7-way with the part # 37185. You will plug the 4-ways in together and then to complete the charge wire you would need to run the black wire of the adapter up to the positive post of the vehicle battery through a circuit breaker like part # 9510.

To make it so that the circuit is only active when the key is on you'll need an isolation solenoid part # PK5231201 which will allow the circuit to only come on with the key.

expert reply by: Jameson C